Born 27 November 1935 in Dublin, John Christopher Byrne was the eldest of 13 children. He left Dublin when he was 21 for the English port of Liverpool, working in the docks and joining the community of working class artists who were emerging in the city, influenced by the American Beat writers. Byrne travelled extensively in his youth, doing a variety of jobs, including electrician's mate, Christmas tree feller and teaching English as a Foreign Language in London, Paris, Athens and Istanbul. By the 1960s he found his calling in the underground arts scene, writing poetry and short stories and editing. He was a touring manager for rock bands (for his agent, the American independent record producer Shel Talmy, who managed the Who and the Kinks). Byrne also performed as part of a surreal performing act The Poisoned Bellows with Spike Hawkins, performing in clubs and at the Edinburgh Festival.

In the 1960s, now based in London, Byrne worked as a literary editor and wrote poetry and short stories, including science fiction which was published in the UK magazines Science Fantasy and it's successor Impulse (his stories appeared alongside those of J. G. Ballard, Thom Keyes and EC Tubb). One story was included in Judith Merrill's The Best Of Science Fiction 1965-6. His science fiction embraced the "new wave" of British 1960s science fiction, along with the prevailing 1960s counterculture- experimental and artistic aspirations, political subtexts, psychedelic drugs and sexual themes, rather than the traditional technological concepts of science fiction. He wrote a best selling novel, Groupie, with Jenny Fabian in 1969; the title popularised the term in the UK and US, and featured the sex, drugs and rock 'n roll lifestyle around groups such as Pink Floyd (named pseudonymously in the novel). In 2003 he began a sequel to Groupie with Fabian, titled Out Of Time.

Byrne began script writing in the late 1960s, with uncredited rewrites for low budget movies. In 1970 he wrote Season Of The Witch for the BBC. He scripted the films Adolf Hitler, My Part In His Downfall (1972), and Rosie Is My Relative (1976). After Space 1999 Year One, he wrote Anderson's Into Infinity. In 1980 he was considered to take over as script editor for Dr Who (from Douglas Adams); in the event, he wrote three episodes (all to a lesser or greater extent rewritten in-house): The Keeper Of Traken, 1981, Arc Of Infinity, 1983, Warriors Of The Deep, 1984. He also contributed a script for a prequel to Traken entitled Guardians of Prophecy, which was never filmed. Byrne later wrote the script for a Dr Who movie in 1990. He wrote three episodes of Tales Of The Unexpected (1980, 1982).

Warriors Of The Deep director Pennant Roberts said "I fancy it was a Space 1999 script which had been translated into the Doctor Who format... It certainly had the appearance of being a space series which had been arbitrarily transferred underwater. It was just a lot of battles, one special effect on top of another." Byrne denied it was a story idea from 1999, but he had borrowed concepts. It is set on an underwater base, instead of a moonbase (although Byrne's original conception was closer to Alien than the white walled sets actually built). "In a vain attempt to keep the human dimension in the conflict, and out of the control of the computers, they had an intermediary between themselves and the machines. This was an idea that had stayed with me since I worked on a Space 1999 story (by Christopher Penfold) called The Guardian of Piri. This was in no way connected and was a different situation, but there was this character who was logged in to computers in this way"

Byrne was the main writer and story consultant on the series All Creatures Great & Small (1976, 1978, 1985, 1988, 1989, 1990, 38 episodes). The success of the series led him to work on other popular comedy-drama series, such as the zoo vet series One By One (1987, 13 episodes) and the country vet series Noah's Ark (1997-1998, which he created and wrote 9 episodes of the two series). In 1992 he created another series based in period rural Yorkshire, Heartbeat, adapting the concept from the "Constable" book series by Nicholas Rhea. He was principle scriptwriter for the hit series from 1992 for 17 series, until 2007. The series was consistently the best rated drama series in the UK, only beaten by the top soap operas. He also wrote the film To Die For (1995). He has written and lectured on political issues (especially Yugoslavia) and is interested in Celtic mythology. In 1999 he wrote the short film Message From Moonbase Alpha.

Byrne married his wife, Sandy, in the 1970s and they had three sons. He died in April 2008.

Space: 1999

Byrne was initially contacted by Christopher Penfold when the series was to be the second series of UFO. He left during the hiatus and returned just 2 weeks before filming began. Initially he was to stay just 6 weeks as script editor and rewriting Art Wallace's script of the second episode. He became story consultant, but was less involved with Year 2 as he had got married and was renovating his Norfolk cottage. Byrne used the names of several friends in the series: fellow writer Thom Keyes was called by inaudible announcements in several episodes; Keyes's wife Regina von Kesslann was a character in Another Time Another Place; Spike Hawkins (former husband of Jenny Fabian) became a guard in the unfilmed Face Of Eden; Steve Abrams became a pilot in Voyager's Return. He lived with many of these people in a hippy commune in the early 1970s.

From a post to rec.arts.tv.uk, 21st Jan 1996: As for Space, I loved every moment of the years I spent on it. For all its faults, I prefer the first series. Limited humans struggling to survive in an unknown and frightening universe was more interesting to write. In the first season they were people like us. In the second they were close to being regular space voyaging jocks who knew pretty much all the answers. I was scheduled to story consult and write for the second season - but Freddy's arrival put the damper on that. I stayed on to write three episodes, but decided that getting married was infinitely more fun than working with Freddy. :) I liked him personally - but our views were irreconcilable where Space was concerned.

Favourite Eps? Hard to say. The circumstances of how they came to be written and made colours my judgement. But I do have a great fondness for the tragic immortal `presence' in the `Immunity Syndrome'. Also, Mission Of The Darians, Troubled Spirit - both for the themes and the way they were structured. Testament Of Arcadia still generated a spiritual frisson when I last saw it - though at that time money was tight and we were lumbered with Italian leading men who could hardly speak a word of English. Voyager also has its moments for me. Force Of Life for David Tomblin's pace, energy and visual impact. I thought Maya was a mistake - not the actress or the character - just the unlimited nature of the shape changing. I know I wrote her into the series with these powers fully grown, but that was the front office at work.

I thought most of the directors brilliant - notably Charles Crichton and David Tomblin, who unfortunately later chose to first assistant direct for others, notably Spielberg. Ray Austin was another favourite director of mine. My greatest regret is that I lost the only existing copy of the script I wrote during the hiatus between series I & 2 - Children Of The Gods. Gerry thought it the best I had written to date. But Freddy elbowed its production and somehow the typescripts were lost during my move from Pinewood.

I haven't seen the episodes for a very long time. Nor have I the foggiest notion how they come across to people watching them today. Certainly, I thought at the time - still do - that we were doing something very special during the time before Freddy. The somewhat negative flaky premise - the moon travelling through space under its own steam - was swiftly discounted and the possibilities exploited. Time pressure denied the series the often exhaustive preparations that go into productions of this type. Perhaps we were lucky in this respect because over-produced series have the smack of death when they finally fetch up on our screens. As it was, we were literally making it up as we went along. The writers, like the Alphans themselves, were voyaging into the unknown.

This was reflected in the progression of the first series. The further the Alphans receded from Earth, with all its apparent certainties, the more uncertain and challenging their lot became. They were confronting problems - moral, ethical, human, scientific - they didn't really understand. Or, if they did, their understanding was never more than superficial.

This was a crucial element in the first series - the sense that often there are no set and definitive answers. To do so meant first understanding the question, and often the Alphans didn't. Frequently they were dealing with matters the nature of which was beyond their earthly limitations. Wisdom, when it did surface, was an acknowledgement of what they didn't know, rather than what they did. In the second Freddy season, there was sense of this in my Immunity Syndrome, which is why I'm fond of it - it's an indication of the type of episode a non-Freddy series two would have included.

(2002 interview) Just as the knowledge of the Alphans expanded, so the same was happening to us. We became the invisible members of Moonbase Alpha. The scripts were being written in this consecutive fashion, the experience gained in one was feeding into the next, the sense of discovery was our sense of discovery.